If the British television presenter is found in contempt, all his comments on the witness stand, as well as his controversial 2003 documentary about Mr Jackson, could be struck from the court record.

That could deliver a severe blow to the prosecution’s case, which is based heavily on Mr Bashir’s 100-minute film. As the first evidence to be presented to the jury, the documentary was thought to be the prosecution’s strongest card.

The battle over Mr Bashir’s right to not answer questions began as soon as the short, unassuming journalist entered the Santa Maria courtroom where Mr Jackson is on trial for child abuse, extortion and abduction. The dispute turned into open warfare, however, after Mr Bashir’s documentary, Living with Michael Jackson, was shown to the jury. That was when cross-examination began of Mr Bashir, a former BBC journalist who now works for America’s ABC News.

Questioning was led by Thomas Mesereau Jr, chief defence lawyer for Mr Jackson. Mr Mesereau attempted to destroy Mr Bashir’s credibility with questions about complaints made against him in Britain for unfairness and misrepresentation, and allegations that he had once forged signatures.

Mr Bashir said that only one complaint had been upheld against him by British broadcasting regulators for a story on a maths prodigy. “I was accused of not representing the entirety of what I was doing to one of the individuals,” he said.

Mr Mesereau countered: “That’s kind of what you’ve been accused of here, right?” The British journalist, repeatedly apologising for being too short to reach the microphone on the witness stand, declined to answer four of Mr Mesereau’s direct questions before the break for lunch.

Mr Bashir also declined to supply a yes or no answer when Mr Mesereau asked him if he had discussed his appearance at the trial with anyone other than his lawyer. In an openly hostile exchange, Mr Mesereau repeatedly asked the same question, in a manner of withering sarcasm.

Mr Bashir remained polite and composed throughout, addressing Mr Mesereau as “Sir” and explaining that his subpoena to appear in court was an international news story and that he might have discussed his appearance with another journalist. However, he said he could not recall precisely. “I want to be completely unequivocal,” Mr Bashir said.

Mr Bashir, who flew from New York to Santa Maria to appear at the trial, argued through his lawyer that he was protected from contempt of court charges by California “shield law”. This law protects journalists from being charged with contempt of court if they refuse to answer questions about their sources, or the way they gather news, while on the witness stand.

“With the greatest respect to the court we’re concerned that (these questions) could harm the ability of journalists to gather information,” Theodore Boutrous, the lawyer acting for Mr Bashir and American media companies, said.

However, the judge in the case, Rodney Melville, refused to make a decision, saying he would review the questions that Mr Bashir refused to answer and decide later whether he was in contempt. “It’s a really ticklish area,” the judge said.

Mr Bashir, who won Mr Jackson’s confidence with a hand-written letter of recommendation from the late Diana, Princess of Wales, arrived at the Santa Maria courthouse at about 9.15am in a black Jaguar. He walked with his head held down past a popping and fizzing wall of paparazzi, into the court building.

When he took the stand Mr Jackson became tense and agitated, dabbing at his eyes with a tissue. The reporter raised his right hand, then spelled his name. Mr Bashir avoided the gaze of the pop star, who has not seen the journalist since the filming of Living with Michael Jackson was completed in January 2003. In the film, Mr Jackson admitted to sharing his bed with young boys, leading indirectly to his trial on child molestation charges.

Earlier in the morning, the white-haired Mr Mesereau finished his opening statement by rejecting Mr Sneddon’s ten-count indictment. In response to claims that Mr Jackson gave alcohol to his accuser — a cancer survivor named Gavin Arvizo, who was 13 years old at the time of the alleged molestation, Mr Mesereau said that Gavin and his two siblings ran wild around Mr Jackson’s Neverland ranch, causing havoc.

“The Arvizo kids were out of control,” he said.

Mr Bashir left the stand in the afternoon after refusing to answer more questions. He is expected to be called back after the judge has decided whether or not he is protected by the shield law.

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